In a future where we use technology sustainable, there will be more vehicles, not less. Each will be used for what it is best at.

My current collection of vehicles (in Wyoming) is almost like your wish list: 1) Prius for travel, 2) Subaru Forester for getting around in snow and ice and as a second vehicle when the Prius is in use, 3) Ford F150 4WD for plowing snow and hauling big loads, and 4) motorcycle for all trips when the road is dry and I am not carrying much stuff. The SRK will replace the motorcycle, and I expect it to be an all season vehicle. With 2WD, software differential, and 70% of weight on the drive wheels, it should be very good on snow and ice.

More vehicles in the future, I suspect they will be more individualized. More single seat vehicles for single travelers. The only thing that keeps me from more vehicles right now is the cost of insurance.

Very similar list. If I need a travel vehicle, Toyota Camry hybrid @ 53 mpg for the win! SRK in snow... hmmm. 70% of successful snow travel is good snow tires. I admit, I am curious.
I will question the 30% weight on the rear tire in snow. I have to wonder how well the rear wheel will track, especially in corners.

I think most of the directional stability for the SRK on snow will come from the software differential. The rear wheel could be a hockey puck and it would still be stable and controllable. Since it uses car tires, snow tires could be fitted. For any vehicle, driving habits must be adjusted to match the vehicle. Take it out on an empty snowy parking lot and spin it around.

If you have more vehicles, you aren't generally doing more total driving. Insurance should account for that. Shop around.